STCF04 Datasheet, PDF (23/43 Pages) STMicroelectronics – Cell phones and smartphones

STCF04
Description of the internal registers
9
Description of the internal registers
Table 9. I²C register mapping
Register name
SUB address (hex)
CMD_REG
00
FL_REG
01
AUX_REG
02
STAT_REG
03
FTR_REG
04
TRCH_REG
05
Operation
R/W
R/W
R/W
R only
R/W
R/W
Description
Commands
Flash register
Auxiliary LED
Status register
Features
Torch register
Note:
All the registers can be read only when the PWR_ON bit is 1. Reading any register when
PWR_ON = 0, gives 0 regardless of the real value of the register. This concerns command
and feature registers in Monitoring mode and Shutdown + NTC mode.
9.1
Commands (CMD_REG) 00(hex)
Table 10. Command register
CMD_REG
(Write mode)
MSB
LSB
SUB ADD=00 PWR_ON FLASH_ON TCH_ON NTC_ON TCHV_H CHRG MONTR
N/A
Power-ON
RESET value
0
0
0
0
0
0
0
0
9.1.1
9.1.2
9.1.3
PWR_ON
When set, it activates all analog and power internal blocks including the NTC supporting
circuit, and the device is ready to operate (Idle mode). As long as PWR_ON=0, only the I²C
interface is active, minimizing Shutdown mode power consumption.
FLASH_ON
This bit is AND-ed with the FLASH pin to generate the internal signal FL_ON that activates
Flash mode. In this way, both soft-triggering and hard-triggering of the flash are possible. If
soft-triggering (through I²C) is chosen, the FLASH pin is not used and must be kept HIGH
(tied to VBAT). If hard-triggering is chosen, then the FLASH pin must be connected to a
microprocessor I/O devoted to flash timing control, and the FLASH_ON bit must be set in
advance. Both triggering modes can benefit from the internal flash time counter, which uses
the FLASH_ON bit and can work either as a safety shutdown timer or as a flash duration
timer. Flash mode can start only if PWR_ON=1. The LED current is controlled by the value
set by the FDIM_0~2 of the DIM_REG.
TCH_ON
Torch on: when set to 1 from Idle mode, the STCF04 enters Torch mode. The LED current is
controlled by the value set by the TDIM_0~3 of the TORCH_REG.
Doc ID 022927 Rev 3
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